Compounds which correspond to the following general formula are known (see German Offenlegungsschrift No. 2,344,833): ##STR2## wherein
R.sub.1 represents a hydrogen atom or an alkyl radical having from 1 to 4 carbon atoms,
Het represents a nitrogen-containing 5- or 6-membered heterocyclic radical
Z represents a sulphur atom or an oxygen atom, an NH- or methylene group,
m and n represent the value 0 or integers from 1 to 4, and the total of m and n is from 2 to 4,
X represents a COR.sub.3 --, CSR.sub.3 --, SO.sub.2 R.sub.4 -- OR --N.dbd.CHR.sub.5 group, or if Z represents a methylene group, X represents a nitro group, R.sub.3 represents an alkyl or alkoxy radical having from 1 to 4 carbon atoms, an optionally substituted aryl radical, a trifluoromethyl or amino group, and R.sub.4 and R.sub.5 represent an optionally substituted aryl radical, and salts thereof. The entire disclosure of German OS No. 2,344,833 is hereby incorporated by reference and relied upon.
Furthermore, German Offenlegungsschrift No. 2,734,070 discloses aminoalkylfuran derivatives corresponding to the general formula ##STR3## and salts and N-oxides thereof, wherein R.sub.1 and R.sub.2 which may be the same or different, represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl which is interrupted by an oxygen atom or a group ##STR4## wherein R.sub.4 represents hydrogen or lower alkyl, or wherein R.sub.1 and R.sub.2, together with the nitrogen atom to which they are joined, may form a heterocyclic ring which may contain O and/or ##STR5## as heteroatoms, wherein furthermore R.sub.3 represents hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl, X represents --CH.sub.2 --, O or S, Y represents .dbd.S, .dbd.O, .dbd.NR.sub.5 or CHR.sub.6, Alk represents a straight or branched alkylene chain having from 1 to 6 carbon atoms, R.sub.5 represents H, nitro, cyano, lower alkyl, aryl, alkylsulphonyl, or a;rylsulphonyl, R.sub.6 represents nitro, arylsulphonyl or alkylsulphonyl, m represents an integer from 2 to 4 and n represents 1 or 2, or if X represents sulphur or --CH.sub.2 --, n represents 0, 1 or 2. The entire disclosure of German OS No. 2,734,070 is also hereby incorporated by reference and relied upon.
An antihistamine effect of the H.sub.2 -blocker type is specified for these previously known compounds. They prevent the secretion of gastric juice when this is stimulated by histamine-H.sub.2 receptors. However, the activity of these known compounds is only relatively low, but in particular it is only brief.